VFD2041 Technical Manual Revision: 1.
Contents Contents ii 1 Introduction 1.1 What to Expect From the VFD2041 . . 1.2 What Not to Expect From the VFD2041 1.3 Setup for Testing . . . . . . . . . . . . 1.4 Trying Out the VFD2041 . . . . . . . . 1 1 1 1 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4 Bar Graphs and Special Characters 4.1 Command List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1.1 Initialize wide vertical bar graph (254 118) . . . . . . . . . . . . 4.1.2 Initialize narrow vertical bar graph (254 115) . . . . . . . . . . . 4.1.3 Draw vertical bar graph (254 61 [column] [height]) . . . . . . . . 4.1.4 Initialize horizontal bar graph (254 104) . . . . . . . . . . . . . . 4.1.5 Draw horizontal bar graph (254 124 [column] [row] [dir] [length]) 4.1.
1 Introduction The VFD2041 comes equipped with the following features; • • • • • • • • • • • • 20 column by 4 line text display Built in font with provision for up to 8 user defined characters Speeds from 1200 bps to a lighting fast 19.
• A 9 or 25 pin RS-232 serial cable. If using a 25 conductor cable, a 9 to 25 pin adapter will be required. Figure 1: Connections for Testing 1. Refer to the Figure above for the following steps. 2. Wire the connector to the power supply. On most connectors the RED lead will go to +5V and the BLACK lead to GND. NOTE The Manufacturer’s Warranty becomes void if the unit is subjected to over-voltage or reversed polarity. 3. Connect the display to the PC using the serial cable and adapter if required.
Figure 2: Electrical Connections The display has three connectors; Table 1: Connectors & Functions Connector 2 pin 4 pin DB-9F 2.1.1 Function General purpose output Power and I2 C communications RS-232 / power Power Connections Power is applied via pins 1 and 4. Power requirement for standard units is +5 VDC ±0.25V. Units with the wide voltage range option require 8 - 15 VDC. WARNINGS • Do not apply any power with reversed polarization. • Do not apply any voltage other than the specified voltage.
Figure 3: Power Connector Table 2: Connector Pinout Pin 4 Pin 3 Pin 2 Pin 1 2.1.2 Ground SDA (I2 C data) / Rx SCL (I2 C clock) / Tx Vdc Five Volt Modules If the display is used in a PC it then becomes tempting to plug a spare power connector into the unit. Don’t do this! Wiring for the PC power connector and that required for the display are different, as shown in the Figure below.
Figure 5: Five Volt Power Cable 2.1.3 Wide Voltage Range Modules NOTE Do not use this cable unless the display module has the "Wide voltage range" option (option V). Use of the 12 volt power cable with 5 volt modules will damage the module. The 12 volt power cable is designed for use with wide voltage range display modules mounted in a PC. Wiring required for the 12 volt power connector is shown in the Figure below.
2.1.4 Applying Power through the DB-9 Connector Power may be provided to the module by pin 9 of the DB-9 connector instead of through the 4-pin SIP. If power is to be applied using the DB-9, it must be a regulated 5Vdc supply. NOTE This applies to wide voltage units (V and VPT extensions) as well as to standard 5volt units. Figure 8: DB-9 Power To use pin 9 as the power source, the user must solder the 5 volt jumper pad beside the DB-9 connector.
2.2.1 DB-9 Connections A standard DB-9F is provided for RS-232 communications. Power may also be supplied via this connector if desired. Figure 9: RS-232 Power Connector Table 3: RS-232 Pinout Pin Number 2 3 5 2.2.2 Direction Data from VFD Data to VFD - Description Data out (VFD) Data in (VFD) Ground VFD Tx Rx gnd Host Rx Tx gnd Alternate Serial Connection An optional alternate connection header is provided to allow one cable for data and power.
Figure 10: I2 C Connector pinout is as follows; Figure 11: Power Connector Table 4: Connector Pinout Pin 4 Pin 3 Pin 2 Pin 1 2.2.3 Ground Rx Tx Vdc TTL communications The display can be talked to at TTL (logic 0V to +5V) levels. Three modifications have to be made. This will allow TTL communications through the 4-pin SIP header or the DB-9 connector.
Figure 12: I2 C 2.2.4 Configuring RS-232 and I2 C RS-232 baud rate and I2 C address are configured by means of jumpers. Figure 13: RS-232 Jumpers The module is supplied with jumpers J1 and J2 installed, which gives an RS-232 baud rate of 19200 and an I2 C address of 0x5C. • RS-232 port: J0, J1, J2 - control baud rate.
Table 5: Serial Baud Rates Baud Rate 1200 2400 9600 19200 1200 2400 9600 19200 Slave Address 50H 52H 54H 56H 58H 5AH 5CH 5EH 60H 62H 64H 66H 68H 6AH 6CH 6EH J3 out out out out out out out out in in in in in in in in J2 out out out out in in in in out out out out in in in in J1 out out in in out out in in out out in in out out in in J0 out in out in out in out in out in out in out in out in 2.
/ write bit. If we take a standard Phillips 7bit address of 45hex this would be in binary 1000101. This is 7bits. Matrix Orbital would describe the Phillips I2 C address of 45hex as 8Ahex. The read address would be 8Bhex. For more information on Phillips I2 C please visit; ! " #%$ ! & %'() * To communicate by I2 C two jumpers have to be set into the I2 C position above the DB-9 connector.
Figure 16: General Purpose Output Maximum allowable current is 20 mA, which is enforced by the current limiting resistor. If the device being switched has a resistance of 240 ohms or more the corresponding resistor may be shorted. Solder a small jumper wire (wirewrap wire is good) between the two feedthrough holes.
NOTE The GPOs do not have any over current or over / under voltage protection so care must be taken when using them. For instance if the external device is a relay, it must be fully clamped using a diode and capacitor to absorb any generated back electro-motive force (EMF). Figure 18: Clamping a Relay 3 Displaying Text This chapter describes the various text display commands in detail. Before issuing commands to the VFD2041 please read sections 6.2 and 6.3. 3.
Figure 19: Character Set In addition to the built in characters, users may define up to 8 special characters which, once defined, occupy positions 0x00 to 0x07 in the above chart. The display does not have provision to download other fonts. 3.3 Writing Text to the Display When the display receives a character, it displays that character at the position currently defined. The next character sent to the module then advances to the following position on the display.
3.4 Text Commands In this section commands are identified by their names and decimal values. Hex and ASCII equivalents are given in the summary. 3.4.1 Auto line wrap on (254 67) Enables automatic line wrapping. Note that this is not ’word wrapping’ and wraps may occur in the middle of a word. Note that if auto line wrap and auto scroll are both off (default) text will wrap from line 1 to line 3 then 2 then 4. Factory default is OFF. 3.4.2 Auto line wrap off (254 68) Disables automatic line wrapping.
3.4.7 Turn on underline cursor (254 74) Turns on the underline cursor. The cursor shows the current text insertion point. Both underline and blinking cursors may be turned on or off independently. The cursor is off by default. 3.4.8 Turn off underline cursor (254 75) Turns off the underline cursor. Does not affect the blinking block cursor. 3.4.9 Turn on block (blinking) cursor (254 83) Turns on the blinking block cursor. The cursor shows the current text insertion point.
by means of the bar graph commands, or by simply issuing one of the ASCII values 0x00 to 0x07 (which is not prefixed by the command byte, 254). 4.1 Command List 4.1.1 Initialize wide vertical bar graph (254 118) This command defines the 8 special / user characters to be blocks suitable for use in drawing wide (5 pixel) vertical bar graphs. Any previously existing definitions will be lost.
4.1.6 Initialize large digits (254 110) This command defines the 8 special / user characters to be blocks suitable for use in drawing large digits. Any previously existing definitions will be lost. Once this command has been issued, any number of large characters may be placed until the characters are redefined by another command. 4.1.7 Place large digit 254 35 [col] [digit] This command allows the large digits to be drawn on the display screen.
Table 8: Character Values 1 6 11 16 21 26 31 36 2 3 4 7 8 9 12 13 14 17 18 19 22 23 24 27 28 29 32 33 34 37 38 39 Cursor Line 5 10 15 20 25 30 35 40 NOTE Note: Custom characters will be erased if any of the "Initialize bar graph" commands are issued. Example of a degree symbol: ' + # , .-% % &%/ 0 21. %' 3 465879 ! :;* *<#% &= , " ;' ' + # , .-% % &%/ 0 21 >@?A>B5C79 !;D6- :;*E! F# , #F!; ,G!%: * *<#% & ' + # , .-% % &%/ 0 21.
5.1.2 Set brightness (254 89 [brightness]) This command sets the display’s brightness to [brightness], where [brightness] is a value between 0x00 and 0x03 (between 0 and 3) according to the table below. Table 9: Brightness Settings Hex Values 0x00 0x01 0x02 0x03 Brightness 100% 75% 50% 25% Lighting conditions will affect the actual value used for optimal viewing. Brightness is set to 100% by default. 5.1.
5.1.7 Read module type This command will return, over the RS-232 interface in TTL levels only, the model type value of the module. This command returns a 1-byte hex value.
_ ` :;* *a %M%b c ,< ` : * * / 0 a1 ' " F5C7 _ ` :;* *a %M%b c ,< ` : * * / 0 a1 e> df>g5C7 6.3 On Numbers Like all computerized devices, the display operates with commands and values in the form of binary numbers. These binary numbers are arranged in 8 digit (i.e., 8 bit) groups called bytes. The decimal value of a byte may have any value from 0 to 255.
This gives rise to the possibility of confusion when parameters are being set on the display. For example, the GPO ON and OFF commands use a number to indicate which GPO is being controlled. We’re told that acceptable values are 0 to 8. All such parameters must use numeric values (i.e., the actual byte values). If we send the ASCII number 0 by mistake it will actually give the value 48 decimal (30 hex) to the parameter, which is wrong.
Command Underline cursor on Underline cursor off Block cursor on Block cursor off Cursor left Cursor right Syntax FE 4A 254 74 254 ’J’ FE 4B 254 75 254 ’K’ FE 53 254 83 254 ’S’ FE 54 254 84 254 ’T’ FE 4C 254 76 254 ’L’ Default off FE 4D 254 77 254 ’M’ n/a Notes Turns on the underline cursor. Turns off the underline cursor. off n/a Turns on the blinking block cursor. Turns off the blinking block cursor Moves the cursor one position to the left.
Command Initialize thin vertical bar graph Initialize horizontal bar graph Draw vertical bar graph Syntax FE 73 254 115 254 ’s’ FE 68 254 104 254 ’h’ FE 3D [col][length] 254 61 [col][length] 254 ’=’ [col][length] Draw horizontal bar graph FE 7C [c][r][d][length] 254 124 [c][r][d][length] 254 ’|’ [c][r][d][length] Initialize large digits FE 6E 254 110 254 ’n’ FE 23 [col] [digit] 254 23 [col] [digit] 254 ’#’ [col] [digit] Place large digits Define custom character FE 4E [c][8 bytes] 254 78 [c][8 bytes
Command Display on Syntax FE 42 [minutes] 254 66 [minutes] 254 ’B’ [minutes] Default on Display off FE 46 254 70 254 ’F’ FE 99 [brightness] 254 153 [brightness] on FE 57 [gpo #] 254 87 [gpo #] 254 ’W’ [gpo #] FE 37 254 55 254 ’7’ off Set Brightness General purpose output on Read module type 7 0xFF255 see table Notes Display will stay on for [minutes]. If [minutes] = 0 display will stay on permanently. Maximum value for [minutes] is 100. Turns off display Sets display brightness.
Table 20: Electrical Specifications Supply Voltage Supply Current 4.75 - 5.25 Vdc (optional 8 - 15 VDC) 11 mA typical Table 21: Optical Characteristics Number of Characters Matrix format Display Area Character Size Character Pitch Line pitch Dot Size Dot Pitch Color of Illumination 80 (20 characters by 4 lines) 5 x 7 with underline 76.3 x 25.20 mm XxY 2.95 x 4.75 mm (XxY), not including underline 3.55 mm 5.35 mm 0.55 x 0.55 mm (XxY) 0.60 x 0.
Figure 20: Physical Layout Matrix Orbital VFD2041 28
7.2 Options Table 22: Options Available on VFD2041 Inverse Blue VFD Inverse Yellow VFD White backlight with Gray glass (Ice Blue) Extended Temperature Wide Voltage Wide Voltage with Efficient Switching Power Supply 8 WB IY GW E V -VPT Appendix: Glossary Table 23: Appendix: Glossary ASCII Baud Rate Binary Number Bit Bitmap Byte Configuration Matrix Orbital American Standard Code for Information Interchange.
Controller DB-9 Firmware Font Font Metric Hexadecimal I2 C Interface VFD Module Type Value Pixel Pre-Generated Fonts Primitive RS-232 Matrix Orbital The micro-controller or PC used to control the Matrix Orbital display unit The designation of a connector used in the RS-232 interface: 9 pin connector Software (programs or data) that has been written onto read-only memory (ROM). Firmware is a combination of software and hardware.
Scroll Serial Number Serial Port Version Number Volatile Memory Matrix Orbital To view consecutive lines of data on the display screen. The term scroll means that once the screen is full, each new line appears at the bottom edge of the screen and all other lines move up one position. A number that is one of a series and is used for identification of the module A port, or interface, that can be used for serial communication, in which only 1 bit is transmitted at a time.
